Hi there Maggie,
Not sure what age an “older woman” is here so my 2 cents as a Pilates instructor and PT:
As mentioned by the other pros, the reformer involves resistance training as does mat band and ring work. So does standing Pilates: great for balance and strength.
If someone was successfully doing the above 3x a week, depending on the person it may indeed be enough but again as mentioned, we have other variables: bone loss, osteoporosis (contraindicated exercises), age, body weight, joint mobility and ability to perform the exercises?
Hope that helps.
I believe that both can be beneficial and as Christine and Nancy have commented it does depend on the type of pilates. It also depends on where your client is starting from. One thing that I would caution is that some pilates exercises are not safe for people with osteoporosis. Just make sure your client is aware of this if she has low bone density.
Women need strength training, cardio, and flexibility in their exercise program. How much of each is dependent upon the individual, goals, and time available—but in general, strength training of the body should be done 2-3 times per week. I would recommend strength training as a compliment. Pilates classes can vary a lot–so if it is providing that person with an overload and proper resistance, then it will strengthen muscles and bones. Keeping a mix each week of different modes, whether that is Pilates, strength training, walking, aerobics classes, etc… helps to maintain both interest and reduce the risk of injury from any one repeated program.
Keeping the body strong with strength training (safely and with proper progression) helps keep activities of daily life more manageable. You can gain muscle at any age, so it’s never too late to start.
PS–My oldest client right now is 75 years young and loves strength training, particularly cables and TRX exercises. 🙂
Hope this helps.